Closure



W. H. ARMACOST Dec. 22, 1936.

CLOSURE Original Filed June 12, 1933 INVENTOR W/L BUR- H 467756067- BY 741w ATTORNEY Patented Dec. 22, 1936 PATENT OFFICE CLOSURE Wilbur H. Armacost, New York, N. Y., assignor to The Superheater Company, New York, N. Y.

Original application June 12, 1933, Serial No. 675,422, now Patent No. 2,029,284, February 4,

1936. 1935, Serial No. 33,022

1 Claim.

My invention relates to a closure device for tubular structures and has as its object the production of an improved device of this sort.

The present case is a division of my application 5 675,422, filed on June 12, 1933, now Patent No.

2,029,284 of February 4, 1936.

In order that my invention may be readily and fully understood, I will now describe in detail by way of example and in connection with the accompanying drawing a device in accordance with my invention and selected from a number of possible embodiments thereof. In the drawing, 7 Fig. 1 is a .vertical sectional view of a fluid heater in which my improved device is employed.

Fig. 2 is a longitudinal sectional view of one of the closures in accordance with my invention.

The heater illustrated in Fig. l and to which I show the improved closure applied, comprises a gas pass It] through which heating gases fiow vertically when the apparatus is in use. Pass Ill is bounded by walls, two of which appear at I2 and M on opposite sides of pass It).

In the arrangement illustrated, fluid to be heated is introduced through pipes into an intake 5 header 22. From header 22 such fluid flows through serpentine units 24, 24 and intermediate headers 25 to outlet header 26. From header 26 it is discharged by pipe 28. The units 24 have individual substantially horizontal elements 30,

30 30, adjacent elements 30 being connected in pairs at their one ends by return bends 32, 32 and at their other ends by return bends 34, 34.

Features of this heater are more fully described, and claimed in said prior application. The present case is confined to the improved form of the return bends 32.

These return bends are intended to give access to the interior of the elements 30 for the purpose of cleaning the latter. For this purpose they must be capable of being readily opened. They are exposed to the corroding effect of the gases fiowing through pass 10, and the purpose of the present invention is to provide a structure for such return bends in such locations which will permit the opening of the return bend when desired. 7

Each return bend 32 has for this purpose a projecting throat 50 provided with a seat 52 at its outer end which is normally closed by a member 54. For holding the members 54 in place against the internal pressure within the units 34, I have provided a novel arrangement comprising a sleeve 56 provided with internal threads 5611 adapted to turn on to the external threads 50a on the throat 50. At its outer end, the sleeve 56 Divided and this application July 25,

also has internal threads cooperating with the external threads of a pressure applying member 58 whose axis is coaxial with that of throat 50 and the closure member 54 and may be screwed down to contact with the member 54 to hold it 5 firmly in place. Tests have shown that the arrangement just described has the capacity of remaining tight even under sudden changes of temperature. A return bend having the closure arrangement above described applied thereto 10 may have cold water poured on the closure arrangement without causing it to leak. This is a very severe test and I attribute the success of the arrangement illustrated in withstanding such test to the fact that the sleeve 56 has an ample 15 amount of surface in engagement with the throat 53 so that the sleeve inaintains the same temperature as the throat while the bolt or pressure member 58 also has an ample amount of engaging surface with the sleeve and thereby is 20 maintained at the temperature of the sleeve and therefore of the throat. Therefore, the parts once having been put under such pressure to make a tight joint at the seat 52, there is small chance for such pressure to be diminished by 25 changes in temperature of the parts to cause a leak, or for the parts to be overstressed by similar changes so that leakage will occur when the parts regain the same temperature.

In certain classes of apparatus, the heating 30 gases ordinarily carry corrosive substances which are very apt to attack the threads of closure arrangements and damage them and to make it impossible to unscrew the parts. Ordinarily, therefore, the closure arrangements for clean-out structures in apparatus employing serpentine units have wall plates through which the return bends of the units project and packing to prevent the gases from passing between such plates and the elements to the outsides of the plates and there attacking the closure arrangements. Such a structure is comparatively expensive to install and also requires expense for maintenance to insure that such packed joints are maintained tight against the gases. As may be seen in Fig. 1, I have omitted any such plates and packed joints, the closure arrangements and return bends 32 lying in the gas stream. In the arrangement illustrated, I am enabled to do this by providing packing adapted to protect the ends of the threads on the throats 5|] and on the pressure member 58. As shown in Fig. 2, throat 50 has an external collar 60 thereon, and the sleeve 56 is countersunk at its inner end to receive collar 60 and to provide a pocket 6| for receiving compressible asbestos packing 62 or its equivalent between collar 60 and the bottom of pocket Bl. At its outer end, the opening for the bolt 58 is also countersunk at 65 to provide room for a body of packing material 64 similar to 62 on throat 5d. The outer end of bolt 58 also has a collar or enlargement 65 thereon, adapted to fit in countersink 65. It will be obvious that the body of packing 62 will be able to protect threads 5% and a when sleeve 56 is screwed on the throat as, and that, similarly, when bolt 58 is screwed into sleeve 56, the packing 64 will protect the threads on bolt 58 and the threads engaged by them. In order to provide convenient access to the ends of the elements 30 having the clean-out throats 5B thereon, the doorway 42 is closed adjacent the return bends 32 by readily removable doors 68, 58. Preferably the doorway 60 is covered at its outer end by a suitable plate i2 which can be easily taken down and replaced.

.It will be understood that my invention can be used in other relations than those in which it is shown and described herein and that variations may be made in it without departing from its spirit.

What I claim is:

A closure arrangement adapted to resist heating gases and corroding substances carried thereby comprising in combination with a clean-out throat, a sleeve threaded to the outside of said throat, a closure piece within said sleeve and arranged to bear on said throat near the outer end thereof, a pressure member threaded into said sleeve and bearing on said piece to force said piece against said throat, said sleeve having recesses surrounding the outer ends of the threads on said throat and said pressure member, and packing arranged in said recesses so as to protect the threads of said throat, sleeve and pressure member against corrosion.

WILBUR H. ARMACOST. 

